Variable condenser and trimmer therefor



Dec. 15, 1936. s. COHEN 2,063,986

VARIABLE CONDENSER AND TRIMMER THEREFOR Filed May 8, 1934 INVENTOR Jamue/ (0620 ATTO R N EY tatented Dec. 15, 1936 wawec w;

VARIABLE CGNDEN SE12, IfZFJEHtfQ/ZER THEREFQR A miieettiemi May 55,

ehem, Breeittye, N. "R1, mmexut Gememtiem, New at New mix This inventien reietes to condensers, ie-re perticuiefly to con BS6768 germ/fitted with if "ers, and eeiiziensere e. the muliti- F gang type.

variable c densel's oi the s, it is customary te p evizie ei's at eeoh of the sections for adjusting These met condensers .p e singie the other end at which is movable with reeme for capacitance The steticnaiy end the trimmei" piete is secured te the me car/anti the stator i5 cemb by the same mounting screws which fasten We stator t0 the frame. The location of the condenser at either? side of the frame is Ft one side to be very eehe user te shift the tri: eeuse the state? must ecij'uet...1ent is released to IYLOVS nive'etum CE tee stator. in s he eenvement i we a eeime" I te 1X3 eppoeite nee one objeet a detach 7Y3 connected to the 621381 opposite the th e. Way

e1", said. need on the states. 1e. It is also eueteieeiy t0 eeici a. eeldermg to the trimmer and white web a lug not itself use much 21 211, 3 sube'antiel scrap or weste mete! in the eheet "from the trimm r pie-tee punched. In ecsentence with a Hurt-her obj at we invention, a seldeiing lug so formed and lieeeted on the tr mel plate n0 extra metal is required.

Te the accomplishment the foregoing and ether ebjects which will hereinafter appear, my invention consists in the condenser elements emi .5" iette one end of which is stetioneriiy meimte' the :ti'ame,

e eeiatez'ing lugs fer their reietion ere to the eti e hereit more partieul Ty" described 11 the sew to ise define 1e icetien eeeempee. e. elevetie -cS at my m've" taken Fig. 3 is 2. perspective Vie m eceercienee tures ef my i Jet.

5 i crates insulation support for: use with vention;

6 51.5) e seiderimg 2 accordance 1m 1 further tien; and

Fig. 2 is similar View at e Refe ting te the drawing a 13; t0 *gs. ii and 2 thereef,

frame T S, UL circuit see of the we comprises LJ-sfeaped e1 end mates and it is; premiete The partitions each reeei to expose mountings.

straps byeppwpriete tongue eiet' eoimeetiem of eenventioneii type.

The trimmer eendensers T emnpfise e plate 3% the lew end. 32? of which is stetienery and tightly secured to the S, and the tzpe5 per end 34 of which is movable toward and from the adjacent part 36 of the condenser frame for capacitance variation. The adjustment may be made by an adjusting screw 38 passing through an over-size hole 40 in the trimmer plate and threaded into the frame part 36.

.A thin wafer 42 of a suitable insulation, such as mica, may be inserted between the plates of the trimmer condenser.

It has heretofore been the practice to hold the stationary part 32 of the trimmer plate in position by means of screws which are also used to lock the stator combs 22 to the frame F through intermediate pieces of insulation. In accordance with the present invention, the stator section is mounted in the frame by means wholly independent of the trimmer condenser, and rapid removal of the trimmer condenser, or transfer of the same from one side to the other of the condenser frame, is greatly facilitated. The stator is mounted in the frame by means of insulation blocks 44, best shown in Fig. 5. The blocks are generally T-shaped, and the top or cross bar 46 of the block is dimensioned to be received within the channel 28 of the comb. The bottom of channel 28 is cut away or slotted, as shown at 48, to receive the stem 50 of insulation block 44. The comb and block are provided with aligned apertures 52 and 54 respectively, through which the comb and block are permanently locked together by appropriate rivets 56. It will be understood that the block and comb are pref erably thus assembled before applying the comb to the edges of the stator plates.

The bottom wall 58. of the condenser frame is slotted at 60 to receive the lower ends 62 of the insulation blocks. The stator is lowered in place in the frame and accurately located by an appropriate fixture whereupon the outer edges of the bottom 'wall 58 of the condenser frame may be forced inwardly against the blocks 44 with sufficient pressure to bite into theblocks and thus lock the same securely and permanently in place, as is best shown in Fig. 2.

Referring to Figs. 2 and 4, the sheet metal comb 22 is provided with a threaded opening 84. The metal is preferably preliminarily extruded inwardly, as shown at 66, in order to provide increased thread surface while using light'gauge metal. The comb is further provided with a slot 68 formed by striking a lip 10 outwardly from the bottom of channel 28.

The trimmer plate 30 is provided with appropriate means mating with the said parts of the comb. Specifically, the lower end of the stationary part 32 of the trimmer plate is formed into a tongue 12 dimensioned and shaped to pass within the lip 10 until stopped by marginal shoulders 1|. The tongue 12 may, if desired, be bent, as is indicated at 13, to provide a snug fit between the tongue and the comb strap Ill receiving the same. The stationary portion 32 is apertured at 14 in alignment with the threaded hole 64 of the comb. The trimmer plate is also apertured at 15 with large holes clearing the ends of the rivets 56. The trimmer plate may thus be mounted in place with the aid of only a single screw, this screw being indicated at 16 in Figs. 1 and 2. To transfer the trimmer condenser from one side of the frame to the other, it is simply necessary to release adjusting screw 38 and the single mounting screw ",and to thereupon shift the trimmer plate upwardly out of slot 68. The parts are then placed on the opposite side of the condenser in similar relation, the sides of the condenser frame being made symmetrical for this purpose.

It is customary to provide the trimmer plate with a soldering lug formed integrally therewith and ordinarily projecting from the bottom end thereof, thus affording convenient connection to the stator. While the lug itself requires but little metal, it has heretofore caused considerable scrap or waste of metal. In accordance with a further feature of my invention, a soldering lug is provided which is struck outwardly from the middle of the trimmer plate, thus entirely eliminating waste of metal. Specifically, I form a soldering lug which is struck outwardly from the trimmer plate and is connected thereto at the top of the stationary portion 32. The stationary and movable portions of the trimmer plate are joined by an outwardly bent or channeled part 82 which accommodates free movement of the upper part of the plate relative to the lower part of the plate. The lug 80 may be struck from this part of the plate during the formation of the plate, and I find that a suitable lug may be providedfwithout cutting metal from the movable or effective condenser part 34 of the trimmer plate.

To permit connection to be made to the stator on the side of the condenser opposite the trimmer, I provide additional soldering lugs 84, best shown in Figs. 2 and 6. Each lug 84 is formed integrally with and bent outwardly from a body member 86. The lower end of body 88 is formed much like the lower end of the trimmer plate, it being provided with a tongue 4! adapted to fit snugly within the slot 68 or lip III. the mounting of the lug on the comb, the body It may be apertured to receive a mounting screw like the screw 16 used with the trimmer plate. If desired, the construction may be further ,cheapened by striking a tab inwardly from body 86 and dispensing with the mounting screw. The tab 90 is opposed to tongue 88 and jams within the threaded hole 64 of the comb 12. It will be understood that the complete lug may be forced in place or removed, as desired, and that when pressed homev it is held securely by the upward pressure of the tab 90 and the downward pressure of the shoulders 89 at each side of the tongue 88.

. Of course, a screw like screw 16 of the trimmer plate may be used to hold the soldering lug in place. In such case the lug is made as shown in Fig. 7, the body of the lug being perforated at 92 to receive the screw.

In addition to the slot 44 (Fig. 4) adjacent the lower strap 26 of the comb 22, I may provide an additional slot 94 adjacent the upper strap 24. These slots are of advantage in affording a very slight yieldability oi the straps for selfadjustment during assembly of the condenser.

The large radius ends of the rotor plates are spaced and joined by the conventional strap 46 (Fig. 2), but in the present case the strapis arranged at an angle and within the general outline of the plate. In effect, the rotor assembly is beveled. The stator plates are matingly beveled at 98.. I find that this construction minimizes loss of plate area, while obtaining best uti lization and least waste of metal when punching the plates from a continuous sheet of material. For convenience, I may refer to the angle or bevel relative to the straight sides of plates generally defined by a straight and a curved edge. but ob-' viously no limitation as to the exactor detailed shapes of the plates is intended.

To complete It is believed that the mode of constructing 75 and using, as W811 as the many advantages 01' my improved condenser csnstmctian, will Fee apgsarent from "the fmnezi; mg detailed desarsr thereof. The cam'iemm' pmvided WW1 mer plates which family implied in ye moved fmm the comie wiizheut in any way finosening the mom. he amtor m aha can fienser frame. ammenser thus shifted from mm as w withmzi; 'upsett .i'wauiam 0 we m gsiias'e 3. L A 3.3 S1,

have i: 4.

mama support- 7Q gemienfiy of the S 312G111 i-awer p0 within a 1 h mmrtinw cf the 5. A variable c-nndenser cal uprising a. frame, a rats? supparted thereby, plm'afizy @rf plates and samba cmmmtmg the'edges red to farm a statm' assembiy, ear/=11 wmb 528;. :5 9f sheet metal shaped.

a leaves? strap, 2m between, a, block: 0f ins 31ml martian, meam 3&0 frame in m Eel? to 37.10301 plate immchng a @diustable upper pm alumna & bottom imagmessefl mum-Melly fi'e'sm mmia, and a ssingie ere" mfi'iznm parizmn 0f we cnmb.

A variable sandens-sy aw? wppmted theifeky and 120mm 00 se'aar assemE-a through the bottom portion 0! said trimmer plate and into the comb, said comb being extruded inwardly and threaded to receive the screw.

9. A variable condenser comprising a frame, a rotor supported thereby, a plurality oi stator plates and combs connecting the edges thereof to form a stator assembly, means mounting the stator in place within the frame, a soldering lug, and integrally formed mating means on said comb and lug for holding the lug on the comb.

10. A variable condenser comprising a frame, a rotor supported thereby, a plurality of stator plates and combs connecting the edges thereof to form a stator assembly, each comb being formed of sheet metal shaped and bent to form an upper strap, a lower strap, and a channel portion therebetween, a block of insulation secured to the channel portion and to the frame in order to hold the stator in place, a soldering lug comprising a body portion and an outwardly projecting lug, said body portion and said comb having integral mating means for holding the lug on the comb.

11. A variable condenser comprising a frame, a rotor supported thereby, av plurality oi stator plates and combs connecting the edges thereof to form a stator assembly, each comb being formed of sheet metal shaped and bent to form an upper strap, a lower-strap, and a channel portion therebetwecn, a block of insulation secured to the channel portion, means securing the blocks to the frame in order to hold the stator in place, a soldering lug comprising a body portion and an outwardly projecting lug formed integrally therewith, said body portion including a tongue adapted to be received within a slot formed on the comb, and an inwardly struck tab adapted to be received within a hole formed in the comb.

aoeapse 12. A variable condenser comprising a frame, a rotor supported thereby, a plurality of stator plates and combs connecting the edges thereof to term a stator assembly, each comb being formed 0! sheet metal shaped and bent to form an upper strap, a lower strap extending-in a di-- rection parallel to the upper strap but lying in an angularly related plane, and an outwardly bent channel-shaped portion between said straps, a T-shaped block 0! insulation the upper bar of which is received within the channel and'the stem oi which passes downwardly through the bottom wall of the channel, rivets permanently locking the comb and insulation block together, means securing said insulation blocks to the frame in order to hold the stator permanently in place, a detachable soldering lug comprising a body portion and an outwardly projecting lug formed intgerally therewith, the lower edge of said body portion being formed into a tongue adapted to be received within an outwardly pressed lip formed on the comb, the upper part of said body portion being struck inwardly to form a tab adapted to be received within a threaded hole formed in the comb, said lug being locked in place between the lip and thread by the opposed tongue and tab. I

13. A spacer and support member or comb tor a variable condenser, said comb comprising a piece oi sheet metal shaped and bent to form an upper holding portion or strap, a lower holding portion or strap, an outwardly bent channel portion interconnecting said lower and upper straps. the channel portion being longitudinally slotted adjacent the. straps to provide slight yieldability oi the straps.

SAMUEL COHEN. 

